2012-13185. Designation of Areas for Air Quality Planning Purposes; State of Arizona; Pinal County; PM10

AGENCY:

Environmental Protection Agency (EPA).

ACTION:

Final rule.

SUMMARY:

Pursuant to section 107(d)(3) of the Clean Air Act, the EPA is redesignating from “unclassifiable” to “nonattainment” an area in western Pinal County, Arizona, for the 1987 national ambient air quality standard for particles with an aerodynamic diameter less than or equal to a nominal 10 micrometers (PM₁₀), and therefore also revising the boundaries of the existing “rest of state” unclassifiable area. The EPA's establishment of this new PM₁₀ nonattainment area, referred to as “West Pinal,” is based on numerous recorded violations of the PM₁₀ standard at various monitoring sites within the county. With the exception of Indian country and certain Federal lands, the EPA's nonattainment area boundaries generally encompass the land geographically located within Pinal County north of the east-west line defined by the southern line of Township 9 South, Gila and Salt River Baseline and Meridian, and west of the north-south line defined by the eastern line of Range 8 East, except where the boundary extends farther east in the Florence and Picacho Peak areas. The effect of this action is to establish and delineate a new PM₁₀ nonattainment area within Pinal County and thereby to impose certain planning requirements on the State of Arizona to reduce PM₁₀ concentrations within this area, including, but not limited to, the requirement to submit, within 18 months of redesignation, a revision to the Arizona state implementation plan that provides for attainment of the PM₁₀ standard as expeditiously as practicable but no later than the end of the sixth calendar year after redesignation.

DATES:

This rule is effective on July 2, 2012.

ADDRESSES:

EPA has established docket number EPA-R09-OAR-2010-0491 for this action. Generally, documents in the docket for this action are available electronically at http://www.regulations.gov or in hard copy at EPA Region IX, 75 Hawthorne Street, San Francisco, California. While all documents in the docket are listed at http://www.regulations.gov,, some information may be publicly available only at the hard copy location (e.g., copyrighted material, large maps, multi-volume reports), and some may not be available in either location (e.g., confidential business information (CBI)). To inspect the hard copy materials, please schedule an appointment during normal business hours with the contact listed in the FOR FURTHER INFORMATION CONTACT section.

FOR FURTHER INFORMATION CONTACT:

Ginger Vagenas, EPA Region IX, [phone], [e-mail].

SUPPLEMENTARY INFORMATION:

Throughout this document, “we,” “us,” and “our” refer to EPA.

Table of Contents

I. Background

II. Proposed Action

III. Public Comment and EPA Responses

IV. Final Action

V. Statutory and Executive Order Reviews

I. Background

On July 1, 1987, the EPA revised the national ambient air quality standards (NAAQS or “standards”) for particulate matter (52 FR 24634), replacing total suspended particulates as the indicator for particulate matter with a new indicator called PM₁₀ that includes only those particles with an aerodynamic diameter less than or equal to a nominal 10 micrometers.^[1] In order to attain the NAAQS for 24-hour PM₁₀, an air quality monitor cannot measure levels of PM₁₀ greater than 150 micrograms per cubic meter (μg/m³) more than once per year on average over a consecutive three-year period. The rate of expected exceedances indicates whether a monitor attains the air quality standard.

Most of Pinal County, Arizona, including the area that is the subject of today's action, was included in the “rest of state” area, which was designated “unclassifiable” for PM₁₀ by operation of law upon enactment of the 1990 amendments to the Clean Air Act (CAA or “Act”).^[2] See section 107(d)(4)(B)(iii). The PM₁₀ designations established by operation of law under the CAA, as amended in 1990, are known as “initial” designations. The CAA grants the EPA the authority to change the designation of, or “redesignate,” such areas in light of changes in circumstances. More specifically, CAA section 107(d)(3) authorizes the EPA to revise the designation of areas (or portions thereof) on the basis of air quality data, planning and control considerations, or any other air-quality-related considerations that the EPA deems appropriate. Pursuant to CAA section 107(d)(3), the EPA in the past has redesignated certain areas in Arizona to nonattainment for the PM₁₀ NAAQS, including the Payson and Bullhead City areas. See 56 FR 16274 (April 22, 1991); and 58 FR 67334 (December 21, 1993).

On October 14, 2009, under CAA section 107(d)(3)(A), the EPA notified the Governor of Arizona and tribal leaders of the four Indian Tribes (whose Indian country is located entirely, or in part, within Pinal County) that the designation for Pinal County, and any nearby areas that may be contributing to the monitored violations in Pinal County, should be revised (“EPA's notification”). Our decision to initiate the redesignation process stemmed from review of 2006-2008 ambient PM₁₀ monitoring data from PM₁₀ monitoring stations within the county that showed widespread, frequent, and in some instances, severe, violations of the PM₁₀ standard.^[3]

Pursuant to section 107(d)(3)(B) of the Act, in a letter dated March 23, 2010, the Governor of Arizona responded to the EPA's notification with a recommendation for a partial-county nonattainment area.^[4]

The boundaries of the prospective PM₁₀ nonattainment area recommended by the Governor of Arizona encompass a portion of central and western Pinal County, and form an area that resembles a backwards “L.” ^[5] See figure 2 of the EPA's Technical Support Document ^[6] (TSD) for a map of both the State's recommended boundaries as well as the EPA's proposed boundaries. The state-recommended area includes all or most of the cities of Maricopa, Coolidge, Casa Grande, and the Pinal County portion of the town of Queen Creek, as well as the western-most portion of the town of Florence and the northern-most portion of the city of Eloy. The State recommends including an area that at its western-most boundary includes nearly all of the City of Maricopa. The State-recommended southern boundary is defined by a line that coincides approximately with Interstate 8. The area recommended by the State continues to the east for approximately 35 miles where it extends to the north, including portions of Florence and Coolidge, and the Pinal County portion of Queen Creek, and terminates just south of Apache Junction. The State-recommended eastern boundary is defined by the north-south line between Range 8 East and Range 9 East. The northern boundary follows the county line south from the Apache Junction area and then follows the boundary of the Gila River Indian Reservation to close back around to the recommended western boundary. See the Governor's March 23, 2010 letter for the legal description of the State's recommended boundaries by township and range and for an enclosed map illustrating this area.

In a letter dated February 11, 2010, the Tohono O'odham Nation (TON) responded to the EPA's December 30, 2009 letter concerning the PM₁₀ designation in Pinal County with a recommendation that the TON land within Pinal County be designated attainment/unclassifiable for PM₁₀. In a letter dated September 2, 2010 the Ak-Chin Indian Community responded to the EPA's December 30, 2009 letter concerning the PM₁₀ designation of Pinal County with a recommendation that the Ak-Chin lands be designated attainment/unclassifiable. The Gila River Indian Community and the San Carlos Apache Tribe did not submit recommendations.

II. Proposed Action

On October 1, 2010 (75 FR 60680), pursuant to section 107(d)(3) of the CAA, the EPA proposed to redesignate from “unclassifiable” to “nonattainment” an area generally covering the western half of Pinal County, Arizona, for the 1987 PM₁₀ NAAQS, and to make a corresponding revision to the boundaries of the existing “rest of state” unclassifiable area. The EPA's proposed boundaries for the nonattainment area encompassed all of the area recommended by the State of Arizona, but extended farther to the east and south, and to a lesser degree, to the north and west. The EPA's proposed boundaries encompassed all land geographically located within Pinal County west of the north-south line defined by the boundary between Range 10 East and Range 11 East, but excluded TON's main reservation and the Apache Junction portion of the existing Phoenix PM₁₀ nonattainment area. See figure 2 of the EPA's TSD for a map showing our proposed boundaries.

As explained in our October 1, 2010 proposed rule (75 FR at 60686), and more fully in the TSD for the proposal, we believe that the State's recommended boundaries would not encompass the full geographic area from which emissions-generating activities contribute to the monitored PM₁₀ violations. More specifically, EPA's proposal stated that the Governor's recommended boundaries, which cut through municipalities and contiguous expanses of agricultural fields, excluded sources that have been identified as dominant sources of PM₁₀ and that are contributing to elevated levels of PM₁₀ at violating monitors. In our October 1, 2010 proposal, EPA stated that its proposed boundaries, described above, would encompass the areas in which PM₁₀ violations are being monitored, as well as the areas that contribute to the monitored violations, and that they were thus consistent with the definition of nonattainment areas in CAA section 107(d)(1)(A). Our proposal was based on the EPA's analysis of the factors as set forth in the proposed rule (75 FR at 60682-60686) and in further detail in the TSD for the proposed rule.

With respect to the affected Indian Tribes, for the reasons given in the proposed rule, we proposed to exclude the main TON reservation and the San Carlos Apache Reservation from the PM₁₀ nonattainment area boundaries, but we indicated that we were deferring action on the status of certain other tribal lands located within the area, including the tribal lands of the Ak-Chin Indian Community and the Gila River Indian Community, as well as TON's Florence Village and San Lucy Farms, pending consultation with the affected tribes.

Please see our October 1, 2010 proposed rule and our related TSD for more information about our proposed action and the rationale for our proposed boundaries.

III. Public Comment and EPA Responses

Our October 1, 2010 proposed rule provided for a 30-day comment period, and the EPA received 11 comment letters in response to the proposal, including letters from the Arizona Department of Environmental Quality (ADEQ), the Arizona Game and Fish Department, the Pinal County Air Quality Department, the City of Casa Grande, the Central Arizona Irrigation and Drainage District, the Arizona Public Service Company, several agricultural groups, the Sierra Club, and a member of the general public.

None of the commenters disagreed with the need to redesignate a portion of Pinal County nonattainment for the 1987 24-hour PM₁₀ NAAQS, and none disagreed with EPA's conclusion that sources outside of Pinal County and in the eastern half of Pinal County, including San Carlos Apache lands, do not contribute to violations in the western portion of the county. In addition, none of the commenters disagreed with EPA's conclusion that the activities occurring on the main Tohono O'odham Nation (TON) reservation do not contribute to these violations. Most commenters, however, suggested that the nonattainment area should be smaller than that proposed by the EPA. Nine commenters supported the Governor's recommended boundary, one commenter supported the EPA's proposed boundary, and one commenter suggested that the boundary should include only developed areas that have a relatively high density of human population.

As discussed in more detail below and in our Response to Comments (RTC) document,^[7] the EPA is taking final action today to redesignate from “unclassifiable” to “nonattainment” an area generally covering the western half of Pinal County, Arizona, for the 1987 PM₁₀ NAAQS, and correspondingly, to revise the boundaries of the existing “rest of state” unclassifiable area. In our final action, however, based on our consideration of the comments, including the building permit data provided by Pinal County that documents the extent to which the national recession has slowed growth in Pinal County, and after further review of other relevant factors, such as the geographic distribution of sources of PM₁₀, the EPA is modifying the boundaries it had proposed for the nonattainment area. EPA's final action modifies its previously proposed boundaries in such a way as to reduce the size of the nonattainment area (relative to the area the EPA had proposed) by approximately 36 percent (about 735 square miles). This reduction is principally accounted for by establishing the final boundaries for the nonattainment area so as to exclude the Tonto National Forest (including the Superstition Wilderness Area), portions of the Sonoran Desert National Monument (including the Table Top Wilderness Area), the Ironwood Forest National Monument, and certain less-developed areas. EPA's proposal had included these areas within the nonattainment area boundaries.

In the following paragraphs of this section, we summarize our responses to significant comments that we received on our October 1, 2010 proposed rule. Our full responses to all the comments received can be found in the previously-cited RTC document, which is included in the docket for this rulemaking.

Air Quality Data

Comment: Disagreement over the size of the nonattainment area was primarily based on commenters' views that certain areas should be excluded from the nonattainment area because they are not themselves violating the standard, or because they are not “significantly” contributing to violations in nearby areas.

Response: CAA section 107(d)(1)(A)(i) defines a nonattainment area to include “any area that does not meet (or that contributes to ambient air quality in a nearby area that does not meet)” the NAAQS. Thus, a location is designated nonattainment if its emissions contribute to the air quality in a nearby area that violates the NAAQS, even if that location is not the main cause of violations, and even if it does not contribute to every measured violation. The absence of a violation at a particular monitor does not preclude the possibility of elevated levels of particulate in the vicinity of that monitor or the transport of particulate to a nearby violating area, even if levels do not cause a violation at the monitor itself. A contiguous area can be nonattainment if it is within several miles of a violating monitor and has emissions that travel to that monitor, even if its contribution is not as large as those of locations nearer the monitor.

Exceptional Events

Comment: Two commenters noted that some of the measured exceedances have been flagged as exceptional events ^[8] and suggested that the EPA should not consider a monitor to be violating if all of the exceedances have been flagged as exceptional events. ADEQ stated that its analysis of the most recent monitoring data indicated that if flagged exceptional events were excluded from the monitoring record, four monitors (Casa Grande, Combs School, Coolidge, and Maricopa) would be attaining the standard.

Response: Based on the most recent certified data (2009-2011), seven monitors in Pinal County are violating the 24-hour PM₁₀ standard. EPA regulations do provide that a State may request EPA to exclude data showing exceedances or violations of the national ambient air quality standard that are directly due to an exceptional event from use in determinations, by demonstrating to the EPA's satisfaction that such event caused a specific air pollution concentration at a particular air quality monitoring location. (40 CFR 58.14) However, as indicated in the proposed rule (75 FR at 60684-60685), even if we were to concur and to exclude from use in determining attainment all of the flagged exceedances, a number of monitors would still violate the standard. Moreover, the emissions sources in the vicinities of the non-violating monitors (i.e., presuming exclusion of the flagged exceedances as caused by exceptional events) are those, such as traffic on paved and unpaved roads, cattle operations, agricultural sources, and construction-generated emissions, that we have determined contribute to violations of the standard elsewhere in the County. Thus, EPA action on State flagged exceptional event claims is not a prerequisite to finalizing this redesignation and establishing appropriate boundaries for the new West Pinal PM₁₀ nonattainment area.

Geographic Distribution of Emissions Sources

Comment: A number of commenters objected to EPA's proposed boundary because, in their view, sources of PM₁₀ emissions leading to monitored violations are located in the western regions of Pinal County, not the east or south [of the Governor's recommended nonattainment area ^[9] ]. They argued that the Governor's recommended boundary included all of the emissions sources that contribute significantly to the PM₁₀ violations, plus an adequate buffer to the south and east.

Commenters pointed to differences in activity levels and the degree of urbanization in areas within and outside the Governor's recommended boundary and argued that the State's preliminary emissions inventory showed that sources in the eastern and/or southern regions of the county do not significantly contribute to violations in other regions of the county.

Response: Arizona's preliminary PM₁₀ inventory and the 2005 National Emissions Inventory, version 2, along with source apportionment studies, identify the sources that contribute to elevated concentrations of PM₁₀. These sources include on-road emissions, cattle operations, agriculture, and construction. According to ADEQ's technical report, these sources of PM₁₀ are located throughout the western portion of Pinal County, including areas to the east and south of the Governor's recommended boundary. See Figures 3-3 and 3-4 of ADEQ's technical report.^[10] The EPA's review of meteorological data indicates that emissions from these areas are transported to the violating monitors 35 to 40% of the time. See the wind rose data collected at the Pinal Air Park as illustrated in Figure 10 of the TSD for the proposal and note the absence of topographic barriers as shown in Figure 11 of the TSD.

As stated above, CAA defines a nonattainment area to include a nearby area that contributes to air quality in the area where violations are measured. To identify nearby areas that contribute to the measured violations of PM₁₀ in Pinal County, we have used a multi-factor analysis that accounts for, among other factors, emissions data, meteorology, and topography, as described in detail in EPA's TSD for the proposed rule and in the RTC document prepared for this final rule. The use of a multi-factor test in determining which areas contribute to violations in a nearby area was upheld in a case involving designations and nonattainment area boundaries for the PM_2.5 standard, Catawba County v. EPA, 571 F.3d 20, 38-40 (D.C. Cir. 2009), and we believe such a test is appropriate in determining the boundaries of an area to be redesignated to nonattainment for the PM₁₀ standard. Moreover, the Catawba County court rejected arguments that “contributes,” for the purposes of interpreting the geographic extent of nonattainment areas under section 107(d)(1)(A), necessarily connotes a significant causal relationship and upheld EPA's interpretation of “contribute” to mean “sufficiently contribute” and then applying a presumption and multi-factor test precisely to identify those areas that meet the definition. Id. In the context of this action, we have not applied any presumption but otherwise have identified the boundaries of the area to be redesignated to nonattainment for the PM₁₀ standard to include areas determined to be sufficiently contributing through application of a multi-factor test.

Off-Highway Vehicles

Comment: The Arizona Game and Fish Department argued that because ADEQ's technical report states that off-highway vehicle emissions are relatively low and there were no grid cells over the 20 ton per year threshold, the nonattainment area boundary should not include undeveloped lands where off-highway vehicle recreation occurs.

Response: Upon consideration of public comments, the EPA has revised our proposed nonattainment area boundary to minimize the inclusion of areas where available information indicates emissions are relatively low. We have established a final nonattainment area that we believe encompasses the areas in which PM₁₀ violations are being monitored, as well as the areas that contribute to the monitored violations, consistent with the definition of nonattainment areas in CAA section 107(d)(1)(A). While this might result in the inclusion of some lands where off-highway vehicle recreation occurs, it does not dictate the application of controls on or regulation of emissions generated by such activities. Arizona will be required to develop a plan that demonstrates attainment of the PM₁₀ standard, and the relative contribution of various sources and options for control will be considered in that process. That plan will be subject to public review and comment, both at the state level and again when the EPA evaluates the plan for approval or disapproval as a revision to the Arizona state implementation plan (SIP).

Wilderness Areas

Comment: Four commenters objected to the inclusion of the Table Top and Superstition Wilderness areas within the nonattainment area, noting that such areas are generally closed to mechanized equipment and do not include sources that could be contributing to exceedances at the violating monitors. The Arizona Game and Fish Department and ADEQ also argued that, EPA had not adequately justified including these wilderness areas and the Tonto National Forest in the nonattainment area. The Arizona Game and Fish Department requested that the EPA remove these areas and other largely undeveloped, rural areas from the nonattainment boundary.

Response: The EPA agrees that, because the wilderness areas and the Tonto National Forest are generally closed to mechanized equipment and lacking in emissions sources, the areas do not contribute to violations at the monitors elsewhere in Pinal County. As a result, we have finalized boundaries that do not include either of the wilderness areas or any portion of the Tonto National Forest, and we have sought to minimize the inclusion of undeveloped land.

Traffic and Commuting Patterns

Comment: Several commenters believe that EPA's inclusion in the proposed nonattainment area of lands in the western half of Pinal County that lie to the east and south of the Governor's recommended boundary is not justified given the traffic patterns and concentration of roads in this area. Commenters stated that the largest category of PM₁₀ emissions in Pinal County is on-road sources, and noted that current traffic and commuter-related emissions are located primarily in the western portions of the county in the more populated regions of Casa Grande and Maricopa. Another commenter asserted that the number of commuters traveling between Pima and Pinal Counties is significantly less than the number traveling between Maricopa and Pinal counties. One commenter contended that the area south of Interstate 8 does not have any roads that lead to major urban centers, except for Interstate 10, and contended that proximity to Interstate 10 does not cause the Pinal Air Park or Eloy monitors to violate.

Response: Although the EPA and ADEQ inventories differed with respect to the quantity of emissions generated by on-road sources (traveling on paved and unpaved roads), EPA and ADEQ agree that this is the largest category of PM₁₀ emissions in Pinal County. EPA TSD Figure 8 and ADEQ technical report Figure 3-5 illustrate the distribution of commuter traffic and emissions generated by traffic on paved roads. Taken together with the overall distribution of on-road emissions shown in ADEQ's technical report (Figure 3-4), it is evident that on-road traffic (including paved and unpaved roads) is a significant source of emissions in the western half of Pinal County, including areas to the south and east of the Governor's recommended boundary.

The EPA believes that the distribution of emissions from on-road traffic requires extending Arizona's recommended boundary; however, upon further review, we concluded that the comments submitted and further review of available data provide a persuasive case for modifying EPA's proposed boundary. For the final nonattainment area boundaries, we reduced emphasis on the growth and commuting patterns and increased the weight given to emissions- and land-use-related data and thus are not including the southern-most portion of Pinal County, the Table Top and Superstition Wilderness areas, and the largely undisturbed desert areas east of Township 8 East, except where the boundary extends farther to the east to include the Florence area and the Picacho Peak area.

Growth Rates and Patterns

Comment: Several commenters argued that growth forecasts made prior to the economic downturn are no longer reliable given current economic conditions, and that future growth is uncertain. Others noted that actual growth in the area south of the Governor's recommended boundary has been modest, and that this area is unlikely to become a major employment center. These commenters questioned the view EPA expressed in its proposal that future employment and population growth in Pinal County justify including the southern portion of the county in the nonattainment area.

Response: In our final action, after considering the comments submitted on our proposal, EPA has reduced the size of the nonattainment area, relative to what was proposed. As noted above in our response to the previous comment, the final nonattainment boundaries do not include the southern-most portion of Pinal County, the Table Top and Superstition Wilderness areas, and the largely undisturbed desert areas east of Township 8 East, except where the boundary extends farther to the east to include the Florence area and the Picacho Peak area. We are persuaded to shrink the boundary in part based on the building permit data provided by Pinal County that documents the extent to which the national recession has slowed growth generally in Pinal County, and particularly in the Interstate 8 and Interstate 10 corridors. We agree that the recession and the number of homes already in foreclosure will likely delay significant growth in the corridors beyond the five-year horizon for reaching attainment of the standard. The Pinal Air Park monitor, located southwest of Interstate 10 near the southern border of Pinal County, is not included within the final boundary. However, as EPA proposed, the Eloy monitor, is part of the final nonattainment area, because EPA continues to believe that the sources in the Eloy area contribute to violations of the PM₁₀ NAAQS farther north.

Meteorology and Transport

Comment: ADEQ and Pinal County Air Quality (PCAQ) asserted that the meteorological data do not support the EPA's inclusion of the southeastern portion of the nonattainment area. In brief, the comments are: (1) The southeast should not be included, since the Eloy monitor there is not violating; (2) the meteorological data relied on by the EPA do not substantiate transport from the southeast; (3) meteorological data show the cause of PM₁₀ violations is local, not transport from the southeast; and (4) the limited data showing instances where measured exceedances have coincided with southeast winds does not justify including the southeast portion.

Response: EPA has included areas to the southeast of the State's recommended boundary, including those near the Eloy monitor, because of the contribution of southeast emissions to violations recorded at the Casa Grande and Pinal County Housing monitors. The EPA does not agree with the commenters' implicit assumption that the southeast portion must be the sole or main cause of violations in order for it to be included in the nonattainment area. While emissions from the southeast may not cause a violation at Eloy, they still contribute to violations farther northwest.

Our conclusion that the area southeast of the State's boundary in and around Eloy contributes to the violations farther northwest is based on (1) emissions inventory data (see table 3 of the TSD for the proposed rule) that shows that PM₁₀ emissions from traffic on paved and unpaved roads, and agricultural and agricultural activities account for most of the overall inventory in Pinal County; (2) maps illustrating the locations of agricultural uses and paved and unpaved roads (see figure 4 and figure 9 of the TSD, respectively) and showing a concentration of such uses and roads in and around Eloy; (3) a map illustrating the distribution of overall PM₁₀ emissions in the county (see figure 5 of the TSD) and showing similar rates of emissions generated in and around Eloy as the area where violations of the standard occur; meteorological data showing a strong component of winds from the southeast (see figure 10 of the TSD); and the absence of significant topographical barriers to transport from the area in and around Eloy to the area where violations occur (see figure 11 of the TSD). This contribution to violations warrants inclusion of this portion of the county in the nonattainment area.

As discussed in EPA's proposal and in the Meteorology section of the TSD, we agree that it would be desirable to have additional meteorological data available. Nonetheless, EPA believes that there are sufficient meteorological data from the AZMET (Arizona Meteorological Network) stations within and around the proposed area to show that flow from the southeast toward the violating monitors occurs often. The EPA believes that this pattern exists even during the exceedance days discounted by ADEQ and PCAQ.^[11] The available meteorological data, along with the topography and the geographic distribution of sources of PM₁₀ emissions, provide evidence that emissions sources in the southeast contribute to NAAQS violations. EPA has concluded that the nonattainment area boundary should lie further to the southeast than the Governor's recommended boundary, though we have reduced the extent relative to the area we had proposed to include.

Comment: Both ADEQ and PCAQ examined HYSPLIT ^[12] back-trajectories for several high-wind exceedance days, along with hourly concentrations and wind data. From the abrupt changes in wind direction and increases in wind speed that often coincided with large increases in PM₁₀ concentrations, they concluded that the PM₁₀ is due to near-field impacts rather than to long-range transport.

Response: While the analyses performed by ADEQ and Pinal County provide useful information for evaluating the PM₁₀ exceedances, as discussed above, establishing nonattainment area boundaries requires us to take into account more than the sole or main cause of an exceedance. Even if the commenters are correct that on certain occasions “wind-transport from the southeast is not a dominant contributing factor” (ADEQ comments, p.4) and that the data “suggest a typical monsoon storm where local weather contributed to local impacts” (Pinal County comments, p.3), EPA remains convinced by the available evidence that transported emissions from the southeast nonattainment area nevertheless do contribute to exceedances. As discussed in more detail in the TSD for the EPA's proposal and in the RTC document, the EPA believes that the meteorological data provide evidence for such a contribution. Other factors, including the geographic distribution of sources of emissions and the topography of Pinal County also reinforce EPA's determination to include this portion in the nonattainment area.

IV. Final Action

For the reasons provided in the proposed rule and TSD, insofar as not modified here, the Response to Comments document, and this final rule, the EPA is taking final action pursuant to section 107(d)(3) of the Clean Air Act to redesignate an area in western Pinal County, Arizona from “unclassifiable” to “nonattainment” for the 1987 24-hour PM₁₀ standard and is therefore also revising the boundaries of the existing “rest of state” unclassifiable area. EPA's establishment of this new PM₁₀ nonattainment area, referred to as “West Pinal,” is based on numerous recorded violations of the PM₁₀ standard at various monitoring sites within the western portion of the county. With the exception of Indian country and certain Federal lands, the EPA's nonattainment area boundaries generally encompass the land geographically located within Pinal County north of the east-west line defined by the southern line of Township 9 South, Gila and Salt River Baseline and Meridian, and west of the north-south line defined by the eastern line of Range 8 East, except where the boundary extends farther east in the Florence and Picacho Peak areas.^[13] In taking this action, the EPA concludes that the State's recommended boundaries do not encompass the full geographic area from which emissions-generating activities contribute to the monitored PM₁₀ violations. See figure 1 in the RTC document for a map that compares the State's recommended boundaries to the EPA's final boundaries.

For this final action, we reduced the size of the nonattainment area relative to the area for which we proposed redesignation and believe that the final boundaries more closely align the nonattainment area boundaries with the areas in which PM₁₀ violations are being monitored, as well as the areas that contribute to the monitored violations. Our conclusion is based on our analysis of the factors as set forth in the proposed rule and related TSD, and RTC document, with particular weight being given to the locations of those sources, including vehicle travel over paved and unpaved roads, and agricultural and construction activities, that comprise most of the overall PM₁₀ inventory, the frequent occurrence of southeast winds, and the absence of topographical barriers.

We are continuing to defer our decision regarding redesignation of the Ak-Chin and Gila River Indian Community lands, as well as TON's Florence Village and San Lucy Farms, pending consideration of issues unique to tribal lands, completion of formal consultation with the tribal governments, and (in the case of the Gila River Indian Community) further review of air quality monitoring data including an evaluation of exceptional event claims. The existing Phoenix PM₁₀ nonattainment area (including the Apache Junction portion of western Pinal County) is unaffected by this action.

Areas redesignated as nonattainment are subject to the applicable requirements of part D, title I of the Act and will be classified as moderate by operation of law (see section 188(a) of the Act). Within 18 months of the effective date of this redesignation action, the State of Arizona must submit to the EPA an implementation plan for the area containing, among other things, the following requirements: (1) Provisions to assure that reasonably available control measures (including reasonably available control technology) are implemented within 4 years of the redesignation; (2) a permit program meeting the requirements of section 173 governing the construction and operation of new and modified major stationary sources of PM₁₀; (3) quantitative milestones which are to be achieved every 3 years until the area is redesignated attainment and which demonstrates reasonable further progress, as defined in section 171(1), toward timely attainment; and (4) either a demonstration (including air quality modeling) that the plan will provide for attainment of the PM₁₀ NAAQS as expeditiously as practicable, but no later than the end of the sixth calendar year after the area's designation as nonattainment, or a demonstration that attainment by such date is impracticable (see, e.g., section 188(c), 189(a), 189(c), and 172(c) of the Act). We have issued detailed guidance on the statutory requirements applicable to moderate PM₁₀ nonattainment areas [see 57 FR 13498 (April 16, 1992), and 57 FR 18070 (April 28, 1992)].

The State will also be required to submit contingency measures (for the new PM₁₀ nonattainment area), pursuant to section 172(c)(9) of the Act, which are to take effect without further action by the State or the EPA, upon a determination by the EPA that an area has failed to make reasonable further progress or attain the PM₁₀ NAAQS by the applicable attainment date (see 57 FR 13510-13512, 13543-13544). Pursuant to section 172(b) of the Act, the EPA is establishing a deadline for submission of contingency measures to coincide with the submittal date requirement for the other SIP elements discussed above, i.e., 18 months after the effective date of redesignation. Lastly, the new PM₁₀ nonattainment area will be subject to the EPA's general and transportation conformity regulations (40 CFR part 93, subparts A and B) one year from the effective date of redesignation. See section 176(c)(6) of the Act.^[14]

Specifically, this section of the CAA provides areas, that for the first time are designated nonattainment for a given air quality standard, with a one-year grace period before conformity applies with respect to that standard. Because this is the first time that this portion of Pinal County is being designated nonattainment for the PM₁₀ NAAQS, it will have a one-year grace period before conformity applies for the PM₁₀ NAAQS.^[15]

The new West Pinal PM₁₀ nonattainment area would be considered to be a “donut area” because portions of the area in Queen Creek and Apache Junction are within the area covered by a metropolitan planning organization (MPO), the Maricopa Association Governments (MAG) and a portion lies outside of MAG's boundaries. For the purposes of transportation conformity, a donut area is the geographic area outside a metropolitan planning area boundary, but inside the boundary of a designated nonattainment/maintenance area. The transportation conformity requirements for donut areas are generally the same as those for metropolitan areas. However, the MPO would include any projects occurring in the donut area in its regional emissions analysis of the metropolitan transportation plan and Transportation Improvement Program (TIP). Therefore, the one-year grace period applies to donut areas in much the same way that it applies to metropolitan areas. That is, within one year of the effective date of an area's designation, a donut area's projects must be included in the MPO's conformity determination for the metropolitan plan and TIP for those projects to be funded or approved. If, at the conclusion of the one-year grace period, the donut area's projects have not been included in an MPO's conformity determination, the entire nonattainment area's conformity would lapse.^[16]

V. Statutory and Executive Order Reviews

A. Executive Order 12866, Regulatory Planning and Review

Under Executive Order 12866 (58 FR 51735, October 4, 1993), the EPA has determined that redesignation to nonattainment, as well as the establishment of SIP submittal schedules, would result in none of the effects identified in Executive Order 12866, section 3(f). Under section 107(d)(3) of the Act, redesignations to nonattainment are based upon air quality considerations. The redesignation, based upon air quality data showing that West Pinal is not attaining the PM₁₀ standard and upon other air-quality-related considerations, does not, in and of itself, impose any new requirements on any sectors of the economy. Similarly, the establishment of new SIP submittal schedules would merely establish the dates by which SIPs must be submitted, and would not adversely affect entities.

B. Paperwork Reduction Act

This action does not impose an information collection burden under the provisions of the Paperwork Reduction Act, 44 U.S.C. 3501 et seq. Burden is defined at 5 CFR 1320.3(b).

C. Regulatory Flexibility Act

Under the Regulatory Flexibility Act (RFA), 5 U.S.C. 601 et. seq., a redesignation to nonattainment under section 107(d)(3), and the establishment of a SIP submittal schedule for a redesignated area, do not, in and of themselves, directly impose any new requirements on small entities. See Mid-Tex Electric Cooperative, Inc. v. FERC, 773 F.2d 327 (D.C. Cir. 1985) (agency's certification need only consider the rule's impact on entities subject to the requirements of the rule). Instead, this rulemaking simply makes a factual determination and establishes a schedule to require the State to submit SIP revisions, and does not directly regulate any entities. Therefore, pursuant to 5 U.S.C. 605(b), the EPA certifies that today's action does not have a significant impact on a substantial number of small entities within the meaning of those terms for RFA purposes.

D. Unfunded Mandates Reform Act

Under Title II of the Unfunded Mandates Reform Act of 1995 (UMRA), Public Law 104-4, the EPA has concluded that this rule is not likely to result in the promulgation of any Federal mandate that may result in expenditures of $100 million or more for State, local or tribal governments in the aggregate, or for the private sector, in any one year. It is questionable whether a redesignation would constitute a federal mandate in any case. The obligation for the state to revise its State Implementation Plan that arises out of a redesignation is not legally enforceable and at most is a condition for continued receipt of federal highway funds. Therefore, it does not appear that such an action creates any enforceable duty within the meaning of section 421(5)(a)(i) of UMRA (2 U.S.C. 658(5)(a)(i)), and if it does the duty would appear to fall within the exception for a condition of Federal assistance under section 421(5)(a)(i)(I) of UMRA (2 U.S.C. 658(5)(a)(i)(I).

Even if a redesignation were considered a Federal mandate, the anticipated costs resulting from the mandate would not exceed $100 million to either the private sector or state, local and tribal governments. Redesignation of an area to nonattainment does not, in itself, impose any mandates or costs on the private sector, and thus, there is no private sector mandate within the meaning of section 421(7) of UMRA (2 U.S.C. 658(7)). The only cost resulting from the redesignation itself is the cost to the State of Arizona of developing, adopting, and submitting any necessary SIP revision. Because that cost will not exceed $100 million, this action (if it is a federal mandate at all) is not subject to the requirements of sections 202 and 205 of UMRA (2 U.S.C. 1532 and 1535). The EPA has also determined that this action would not result in regulatory requirements that might significantly or uniquely affect small governments because only the State would take any action as result of today's rule, and thus the requirements of section 203 (2 U.S.C. 1533) do not apply.

E. Executive Order 13132, Federalism

Executive Order 13132 requires the EPA to develop an accountable process to ensure “meaningful and timely input by State and local officials in the development of regulatory policies that have federalism implications.” This rule will not have substantial direct effects on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government, as specified in Executive Order 13132, because it merely redesignates an area for Clean Air Act planning purposes and does not alter the relationship or the distribution of power and responsibilities established in the Clean Air Act. Thus, the requirements of section 6 of the Executive Order do not apply to this rule.

F. Executive Order 13175, Coordination With Indian Tribal Governments

Executive Order 13175, entitled “Consultation and Coordination with Indian Tribal Governments” (65 FR 67249, November 9, 2000), requires the EPA to develop an accountable process to ensure “meaningful and timely input by tribal officials in the development of regulatory policies that have tribal implications.” The area redesignated in today's action does not include Indian country, and the EPA is deferring action on the Indian country that lies within or adjacent to the newly redesignated area, including the Ak-Chin Indian Reservation, the Pinal County portion of the Gila River Indian Reservation, and TON's Florence Village and San Lucy Farms. In formulating its further action on these areas, the EPA has been communicating with and plans to continue to consult with representatives of the Tribes, as provided in Executive Order 13175. Accordingly, the EPA has addressed Executive Order 13175 to the extent that it applies to this action.

G. Executive Order 13045, Protection of Children From Environmental Health Risks and Safety Risks

This rule is not subject to Executive Order 13045 (“Protection of Children from Environmental Health Risks”) (62 FR 19885, April 23, 1997), because it is not an economically significant regulatory action based on health or safety risks.

H. Executive Order 13211, Actions That Significantly Affect Energy Supply, Distribution, or Use

This rule is not subject to Executive Order 13211, “Actions Concerning Regulations That Significantly Affect Energy Supply, Distribution, or Use” (66 FR 28355, May 22, 2001) because it is not a significant regulatory action under Executive Order 12866.

I. National Technology Transfer and Advancement Act

Section 12 of the National Technology Transfer and Advancement Act (NTTAA) of 1995 requires Federal agencies to evaluate existing technical standards when developing a new regulation. The EPA believes that the requirements of NTTAA are inapplicable to this action because they would be inconsistent with the Clean Air Act.

J. Executive Order 12898, Federal Actions To Address Environmental Justice in Minority Populations and Low-Income Populations

Today's action redesignates an area to nonattainment for an ambient air quality standard. It will not have disproportionately high and adverse effects on any communities in the area, including minority and low-income communities.

K. Congressional Review Act

The Congressional Review Act, 5 U.S.C. section 801 et seq., as added by the Small Business Regulatory Enforcement Fairness Act of 1996, generally provides that before a rule may take effect, the agency promulgating the rule must submit a rule report, which includes a copy of the rule, to each House of the Congress and to the Comptroller General of the United States. The EPA will submit a report containing this rule and other required information to the U.S. Senate, the U.S. House of Representatives, and the Comptroller General of the United States prior to publication of the rule in the Federal Register. A major rule cannot take effect until 60 days after it is published in the Federal Register. This action is not a “major rule” as defined by 5 U.S.C. section 804(2).

L. Petitions for Judicial Review

Under section 307(b)(1) of the Clean Air Act, petitions for judicial review of this action must be filed in the United States Court of Appeals for the appropriate circuit by July 30, 2012. Filing a petition for reconsideration by the Administrator of this final rule does not affect the finality of this rule for the purposes of judicial review nor does it extend the time within which a petition for judicial review may be filed, and shall not postpone the effectiveness of such rule or action. This action may not be challenged later in proceedings to enforce its requirements (see section 307(b)(2)).

List of Subjects in 40 CFR Part 81

• Environmental protection
• Air pollution control
• Intergovernmental relations
• National parks
• Particulate Matter
• Wilderness areas

Authority: 42 U.S.C. 7401 et seq.

Dated: May 22, 2012.

Jared Blumenfeld,

Regional Administrator, Region IX.

Part 81, chapter I, title 40 of the Code of Federal Regulations is amended as follows:

PART 81—[AMENDED]

1. The authority citation for part 81 continues to read as follows:

Authority: 42 U.S.C. 7401 et seq.

Subpart C—Section 107 Attainment Status Designations

2. In § 81.303, the “Arizona-PM-10” table is amended by adding a new entry for “Pinal County” after the entry for “Mohave County (part)” and before the entry for “Rest of State” to read as set forth below.

§ 81.303

Arizona.

* * * * *

Arizona-PM-10

Designated Area	Designation		Classification
	Date	Type	Date	Type
*         *         *         *         *         *         *
Pinal County (part)
West Pinal	7/2/12	Nonattainment	7/2/12	Moderate.
1. Commencing at a point which is the intersection of the western line of Range 2 East, Gila and Salt River Baseline and Meridian, and the northern line of Township 4 South, which is the point of beginning:
2. Thence, proceed easterly along the northern line of Township 4 South to a point where the northern line of Township 4 South intersects the western line of Range 7 East;
3. Thence, northerly along the western line of Range 7 East to a point where the western line of Range 7 East intersects the northern line of Township 3 South;
4. Thence, easterly along the northern line of Township 3 South to a point where the northern line of Township 3 South intersects the western line of Range 8 East;
5. Thence, northerly along the western line of Range 8 East to a point where the western line of Range 8 East intersects the northern line of Township 1 South;
6. Thence, easterly along the northern line of Township 1 South to a point where the northern line of Township 1 South intersects the eastern line of Range 8 East;
7. Thence southerly along the eastern line of Range 8 East to a point where the eastern line of Range 8 East intersects the Northern line of Township 3 South;
8. Thence easterly along the northern line of Township 3 South to a point where the northern line of Township 3 South intersects the eastern line of Range 9 East;
9. Thence southerly along the eastern line of Range 9 east to a point where the eastern line of Range 9 East intersects the northern line of Township 4 South;
10. Thence easterly along the northern line of Township 4 South to a point where the northern line of Township 4 South intersects the eastern line of Range 10 East;
11. Thence southerly along the eastern line of Range 10 East to a point where the eastern line of Range 10 East intersects the southern line of Township 5 South;
12. Thence westerly along the southern line of Township 5 South to a point where the southern line of Township 5 South intersects the eastern line of Range 8 East;
13. Thence southerly along the eastern line of Range 8 East to a point where the eastern line of Range 8 East intersects the northern line of Township 8 South;
14. Thence easterly along the northern line of Township 8 South to a point where the northern line of Township 8 South intersects the eastern line of Range 9 East;
15. Thence southerly along the eastern line of Range 9 east to a point where the eastern line of Range 9 East intersects the northern line of Township 9 South;
16. Thence easterly along the northern line of Township 9 South to a point where the northern line of Township 9 South intersects the eastern line of Range 10 East;
17. Thence southerly along the eastern line of Range 10 East to a point where the eastern line of Range 10 East intersects the southern line of Township 9 South;
18. Thence westerly along the southern line of Township 9 South to a point where the southern line of Township 9 South intersects the western line of Range 7 East;
19. Thence northerly along the western line of Range 7 East to a point where the western line of Range 7 East intersects the southern line of Township 8 South;
20. Thence westerly along the southern line of Township 8 South to a point where the southern line of Township 8 South intersects the western line of Range 6 East;
21. Thence northerly along the western line of Range 6 East to a point where the western line of Range 6 East intersects the southern line of Township 7 South;
22. Thence, westerly along the southern line of Township 7 South to a point where the southern line of Township 7 South intersects the quarter section line common to the southwestern southwest quarter section and the southeastern southwest quarter section of section 34, Range 3 East and Township 7 South;
23. Thence, northerly along the along the quarter section line common to the southwestern southwest quarter section and the southeastern southwest quarter section of sections 34, 27, 22, and 15, Range 3 East and Township 7 South, to a point where the quarter section line common to the southwestern southwest quarter section and the southeastern southwest quarter section of sections 34, 27, 22, and 15, Range 3 East and Township 7 South, intersects the northern line of section 15, Range 3 East and Township 7 South;
24. Thence, westerly along the northern line of sections 15, 16, 17, and 18, Range 3 East and Township 7 South, and the northern line of sections 13, 14, 15, 16, 17, and 18, Range 2 East and Township 7 South, to a point where the northern line of sections 15, 16, 17, and 18, Range 3 East and Township 7 South, and the northern line of sections 13, 14, 15, 16, 17, and 18, Range 2 East and Township 7 South, intersect the western line of Range 2 East, which is the common boundary between Maricopa and Pinal Counties, as described in Arizona Revised Statutes sections 11-109 and 11-113;
25. Thence, northerly along the western line of Range 2 East to the point of beginning which is the point where the western line of Range 2 East intersects the northern line of Township 4 South;
26. Except that portion of the area defined by paragraphs 1 through 25 above that lies within the Ak-Chin Indian Reservation, Gila River Indian Reservation, and the Tohono O'odham Nation's Florence Village and San Lucy Farms.
*         *         *         *         *         *         *

* * * * *

Footnotes

1.  The 1987 p.m.₁₀ standard included a 24-hour (150 micrograms per cubic meter (μg/m3. )) and an annual standard (50 μg/m3. ). In 2006, EPA revoked the annual standard. See 71 FR 61144 (October 17, 2006) and 40 CFR 50.6.

2.  While most of Pinal County was designated “unclassifiable,” two PM₁₀ planning areas that extend into Pinal County were designated under the CAA, as amended in 1990, as “nonattainment:” the Phoenix planning area, which includes the Apache Junction area within Pinal County; and the Hayden/Miami planning area, which includes the northeastern portion of the county. See 56 FR 11101 (March 15, 1991); 56 FR 56694 (November 6, 1991); and 57 FR 56762 (November 30, 1992). In 2007, we approved a redesignation request by the State of Arizona to split the Hayden/Miami PM₁₀ nonattainment area into two separate PM₁₀ nonattainment areas. See 72 FR 14422 (March 28, 2007). Today's proposed action would not affect these pre-existing PM₁₀ nonattainment areas. EPA codifies area designations in 40 CFR part 81. The area designations for the State of Arizona are codified at 40 CFR 81.303.

3.  In a letter dated October 14, 2009, EPA notified the State of Arizona that the PM₁₀ designation in Pinal County should be revised. EPA notified the tribal leaders of the Ak-Chin Indian Community, Gila River Indian Community, San Carlos Apache Tribe, and Tohono O'odham Nation by letters dated December 30, 2009.

4.  Letter from Jan Brewer, Governor of Arizona, to Jared Blumenfeld, Regional Administrator, EPA Region IX, dated March 23, 2010.

5.  The Governor expressly recommended excluding Indian country from the nonattainment area. EPA finds this appropriate, given that the State of Arizona is not authorized to administer programs under the CAA in the affected Indian country. The “backwards L” shape of the recommended area is partly explained by this exclusion because the recommended area partially surrounds Indian country.

6.  EPA Region 9, “Pinal County, Arizona, Area Designation for the 1987 24-hour PM₁₀ National Ambient Air Quality Standard,” Technical Support Document, September 21, 2010.

7.  EPA Region 9, “Response to Comments on the Proposed Action to Redesignate West Pinal County to Nonattainment for the 1987 24-hour PM₁₀ National Ambient Air Quality Standard,” May 2012.

8.  On March 22, 2007, EPA adopted a final rule, Treatment of Data Influenced by Exceptional Events, (EER), to govern the review and handling of certain air quality monitoring data for which the normal planning and regulatory processes are not appropriate. Under the rule, EPA may exclude data from use in determinations of NAAQS exceedances and violations if a state demonstrates that an “exceptional event” caused the exceedances. See 72 FR 13560.

9.  Commenters referring to the “eastern” and “southern” portions of Pinal County appear to be referring to the areas to the east and south of the Governor's recommended nonattainment boundary. In our TSD and in the RTC, EPA's references to the eastern and western portions of Pinal County mean those portions of Pinal County that lie to the east and west of the eastern boundary of EPA's proposed nonattainment area.

10.  ADEQ, “Arizona Air Quality Designations, Technical Support Document, Boundary Recommendation for the Pinal County 24-hour PM₁₀ Nonattainment Area,” March 15, 2010.

11.  In their transport analyses, PCAQ and ADEQ focused on days with the wind trajectory's ending hour oriented from the southeast, but this does not consider other hours during the day that may have had flow from the southeast.

12.  The HYSPLIT (HYbrid Single-Particle Lagrangian Integrated Trajectory) model is used to compute simple air parcel trajectories, dispersion characteristics, and deposition simulations.

13.  Townships to the east of the north-south line defined by the eastern line of Range 8 East that are included in the West Pinal PM₁₀ nonattainment area are: T3S, R9E; T4S, R9E; T4S, R10E; T5S, R9E; and T5S, R10E.

14.  The proposed rule mistakenly stated that any new PM₁₀ nonattainment area would be subject to the EPA's general and transportation conformity regulations upon the effective date of redesignation. See 75 FR at 60688. However, CAA section 176(c)(6) provides a one-year grace period for newly designated (in this case, newly redesignated) nonattainment areas, i.e., for the pollutant for which the area is newly designated (or redesignated) nonattainment. See also, 40 CFR 93.102(d) in EPA's transportation conformity regulation and 40 CFR 93.153(k) in the EPA's general conformity regulation.

15.  For more information on how the one-year grace period applies for transportation conformity purposes, please see the proposed and final rulemaking entitled, “Transportation Conformity Rule Amendments: Minor Revision of 18-Month Requirement for Initial SIP Submissions and Addition of Grace Period for Newly Designated Nonattainment Areas,” published October 5, 2001 (66 FR 50954); and August 6, 2002 (67 FR 50808), respectively. (The proposed and final rule can be found on EPA's transportation conformity Web site: http://www.epa.gov/​otaq/​stateresources/​transconf/​conf-regs-c.htm).

16.  For more information on transportation conformity requirements in donut areas refer to Conformity Implementation in Multi-jurisdictional Nonattainment and Maintenance Areas for Existing and New Air Quality Standards. In particular refer to question 4 in Part 1 and Part 2 of the guidance. The document is available at: http://www.epa.gov/​otaq/​stateresources/​transconf/​policy/​420b04012.pdf.